Starting having trouble with it cutting out, not idling, stalling. Had an FCR off of 2002 CRF450, it leaked fuel with all new gaskets etc, were having problems, so went back to factory carb once we spliced the correct plug on, wiring is correct.

Bike idles cold with choke, gets warm it wont at all, doesnt matter at all where idle screw is set, fully in or fully out. Backfires showing it is lean, I expect the pilot jet and maybe needle to be since this carb was jetted for stock motor plus exhaust/filter previously. We are running a 190 main right now trying to get it to pull up top, used to have I think a 175. It acts like a slow rev limiter, just stops pulling and bum..bum..bum slower than an actual spark cut.

I dont know what his clip is set at or what his pilot jet is currently. We are 3 1/4 turns out on fuel screw, still backfires on decel so I know we need to go bigger there and in with the screw. We are 2000 ft elevation. Plan to check ohm reading on tps, manual says between 490-510 fully open I believe. Plan to pull ignition cover and be sure that flywheel etc is clean/debris free. He has a custom wiring harness built by I believe Derissi racing, Santo is the dudes name, runs GNCC. Not impressed as it came back with no loom, just electrical taped whole thing. We would rather not untape the whole thing shooting in the dark, but may come down to that. Plan to swap coil with good running 05 450r.

Main question is, what size jets reccomended, any other things we should check. I usually am the best in the group jetting wise, but this thing has me stumped because it is so inconsistant, making me think its more spark related. An rpm/throttle range that worked day before in identical whether, will now cut and backfire/blubber next day. We are pulling hair out here!!!

Sorry for long post, appreciate anyone who read the whole thing and has any info.

By NYMXer, Posted August 21, 2009

I'd start with a phone call to Cylinder Works and see what they recommend for a base start on jetting and adjust as needed.

Sign in

Similar Content

This replaces the tube that connects the two carbs on a 1987 Honda XR600R (it may fit other years).
Made in the USA.
Constructed of TPU (solvent safe plastic.)
Its durable stiff abrasion resistant yet flexible enough you never have to worry about breaking it when you're taking apart your carbs.
Fits the o-ring perfectly and slips into the carb nice and tight.
Matches the rear shock coil.
If you would like to buy one contact me via e-mail. They cost $40 Shipping is free (anywhere in the USA). $10 off for active duty or retired military.
Cjmrizek@gmail.com
Make your subject: XR600r

Jeremy Martin Leads the Charge for Wiseco Riders at Daytona Supercross
Christian Craig Turns in Career Best in 450 Competition
MENTOR, Ohio (March 13, 2018) – Jeremy Martin showed the way for Wiseco-sponsored riders in Saturday night’s Monster Energy Daytona Supercross presented by Honda. In a season marred by bad luck and misfortune, Martin put together a near flawless ride to earn his first Eastern Regional 250SX Class podium finish of the season.
Martin qualified eighth for the division’s annual visit to the World Center of Racing, finished fourth in his heat race, and came home second in the 250SX main event, missing his first win of the year by less than a second.

“It’s Daytona, a real man’s track.” said Martin who sits fourth in points. “It was the toughest race of the year as far as fitness. I had to slow down a little bit, halfway through the main. I was getting close to (race winner) Jordon (Smith) and I was starting to think about where I could make a move on him, then I made some mistakes and he got away from me. Couldn’t quite get close again, but it’s good. We’re on the podium and in contention for wins again. That’s something I haven’t been able to say in supercross in a while. We want to get wins and now we know it’s coming.”
Martin’s podium was a bright spot, but the rest of the event was rough for the GEICO Honda/Factory Connection squad. RJ Hampshire crashed hard in his heat race and had to be transported to a local hospital. He injured his back and ribs, but shoulder pain left him with the most concern.
“I felt good on the bike all day,” said Hampshire via his Instagram account. “Had some pretty good speed and my foot just slid off hitting my shifter in those rollers during that heat race. After seeing the pictures from the crash I’m very thankful I didn’t take a shot to my head. I have some fractures in my T3/T4 in my back and ribs. Also have some damage to my lungs which is why I’ll be spending a couple nights in the hospital. I’ll be getting some more checkups this week on the shoulder also.”
Cameron McAdoo, the third member of the team, was unable to compete at Daytona after being sidelined with a hand injury two races ago in Atlanta.
Across the paddock, in the premier 450SX Class, Christian Craig got the call to fill in for Team Honda HRC. With the team’s regular riders Ken Roczen and Cole Seely out with injuries, it was up to Craig to carry the load for the factory team, and the upstart rider didn’t disappoint.
The San Diego native was solid in both qualifying sessions, won his heat race and snagged the holeshot in the division’s main event. After relinquishing the lead to eventual winner Justin Brayton, Craig continued to show he was up for the challenge. The 26-year-old rider raced for second and third for most of the 20-minute-plus-one-lap feature before losing one more spot in the late goings to bring his No. 32 Honda CRF450R home fourth in the final rundown.

“I had a great week testing with the team,” commented Craig. “They came down to Florida right after Atlanta and I feel like we really improved. Just getting more time on the bike and getting more comfortable was huge. I started off race day feeling really good. My qualifying position didn’t really show it, but overall I was happy with my riding. It’s all about having fun out there, and man, that’s what I did tonight. I was up front in the heat race, fell to third, but then the two guys in front took each other out so I ended up winning. You can call it luck or whatever, but I just put myself in a good position to capitalize on people’s mistakes."
“I had a good gate pick and some confidence going into the main. I grabbed the holeshot and led for almost the first lap, but [Justin] Brayton got by me pretty quick. I stayed second for quite a while. I just rode my hardest and did my best. Unfortunately, a couple guys got by me so I ended up fourth. The track was so tough. This is only my second time racing Daytona and last year didn’t go well, so I really wanted to get some revenge this year. It’s better than the week before, but man, I was so close to a podium. I just need to keep putting myself in good positions and work on getting better each weekend.”
Monster Energy AMA Supercross rolls on this weekend when the series visits the “Gateway to the West” for its annual race at the Dome at America’s Center in St. Louis. The 11th of 17 races on the 2018 supercross calendar will be televised live on FS1 Saturday, March 17, beginning at 8 p.m. Eastern Daylight Time, 5 p.m. Pacific.
-30-

So i've only owned 2 strokes and i now own a 01 KX250 that i've fully rebuilt from ground up and i've enjoyed my time on it even though it's been short i rebuilt it in november so not much riding on the old girl but i've been thinking about getting a honda 250 so i found a guy who wants to trade his 06 crf250 for my KX he says he's more of a kawi guy and wants a KX250 2 stroke to go with his kx yard thumper problem is A i don't know much about four strokes he says the bike has 20 hours on it since the previous rebuild is that a lot for a 4 stroke B i heard the 06 is a boggy valve eating &%$#@! with proper maintenance can this be avoided i know a lot of people neglect the bikes so i don't know do any of you guys think this is a good deal or should i keep the kx and if there are any other known issues with this year 250 i should worry about or i just don't want to buy something i immediately have to throw a grand into